﻿#define _CRT_SECURE_NO_WARNINGS 1

//编程初学者入门训练第122题
//BC124 小乐乐是否被叫家长
//https://www.nowcoder.com/practice/cc896ffd90d34c7faa318b04e87adf11?tpId=107&tqId=33405&rp=1&ru=/exam/oj/ta&qru=/exam/oj/ta&sourceUrl=%2Fexam%2Foj%2Fta%3Fpage%3D3%26tpId%3D107%26type%3D107&difficulty=undefined&judgeStatus=undefined&tags=&title=

#include <stdio.h>

int main() {
    int Math = 0;
    int Chinese = 0;
    int English = 0;
    scanf("%d %d %d", &Math, &Chinese, &English);
    int aver = (Math + Chinese + English) / 3;//计算平均分

    if (aver < 60) {
        printf("YES");
    }
    else {
        printf("NO");
    }

    return 0;
}